The Biologic and economic assessment of toxaphene : a report of the toxaphene assessment team to the rebuttable presumption against registration of toxaphene /

"Submitted to the Environmental Protection Agency on September 12, 1977 and November 30, 1978."

Nematosporaceae (Hemiascomycetidae) : taxonomy, pathogenicity, distribution, and vector relations /

Includes bibliographical references (p. 61-71).

Methods for sampling and assessing deposits of insecticidal sprays released over forests /

Issued Nov. 1978.

Radio handbook for extension workers /

"February 1946."

Planning your farmstead wiring and lighting.

Mode of access: Internet.

USDA films for television /

"This publication supersedes Agricultural handbook, no. 131, Television film catalog of the U.S. Department of Agriculture."

Circular.

Mode of access: Internet.

Extension circular.

Mode of access: Internet.

Bulletin.

Mode of access: Internet.

Bulletin.

Nos. 1- comprise the service's 1st Annual report of cooperative extension work in agriculture and home economics, 1914/15.

Cooperative Extension Work

Title Varies: a Report on the Receipts, Expenditures, and Results of Cooperative Extension Work In Agriculture and Home Economics In the U.S; Cooperative Extension Work In Agriculture and Home Economics; Report on Cooperative Extension Work In Agriculture and Home Economics

Annual report

1941/42-1954/55 have also special titles: 1941/42, Agricultural research in Louisiana; 1942/43, Progress through agricultural research; 1943/44-1954/55 Research in agriculture.

"Empezar es haber andado la mitad" : Organización social y condiciones laborales en la Sociedad Vitícola Uruguaya

La Sociedad Vitícola Uruguaya (SVU) se fundó en marzo de 1887 fue parte del proyecto modernizador y diversificador del agro uruguayo impulsado por la Asociación Rural del Uruguay (ARU), entidad corporativa similar a la Sociedad Rural Argentina. Este trabajo analiza los orígenes de la SVU, única entidad de este tipo en Sudamérica, en el marco del desarrollo agrario uruguayo de finales del siglo XIX. También se estudian las condiciones de la mano de obra asalariada, la división de las tareas y la estructura organizacional en los orígenes del establecimiento. El objetivo es analizar cómo un sector de la élite uruguaya, reunida en la ARU, impulsó la creación de la SVU como parte de un modelo de producción capitalista diversificada y basada en una sociedad por acciones en el agro a finales del siglo XIX. La hipótesis que guía este trabajo es que dicho proyecto no sólo tenía como objetivo el desarrollo de la vitivinicultura, sino también, el de servir de modelo sociocultural con el fin de motorizar relaciones sociales capitalistas en el agro y de afincar al "gaucho" en el entorno rural

Phototoxicity of photosystem II (PSII) herbicides to coral

Recent reports of contamination of the Great Barrier Reef Marine Park by herbicides used in antifouling paints and in agriculture have caused concern over the possible effects on corals in nearshore areas. Pulse-Amplitude Modulated (PAM) chlorophyll fluorescence techniques were used to examine changes in the maximum effective quantum yield (ΔF/Fm′) of symbiotic dinoflagellates within the host tissues (in hospite) of the coral Seriatopora hystrix exposed to a number of Photosystem II (PSII) inhibiting herbicides in short-term toxicity tests. The concentration of herbicide required to reduce ΔF/Fm′ by 50% (median effective concentration [EC50]) differed by over 2 orders of magnitude: Irgarol 1051 (0.7 μg l-1) > ametryn (1.7 μg l-1) > diuron (2.3 μg l-1) > hexazinone (8.8 μg l -1) > atrazine (45 μg l-1) > simazine (150 μg l-1) > tebuthiuron (175 μg l-1) > ionynil (> 1 mg l-1). Similar absolute and relative toxicities were observed with colonies of the coral Acropora formosa (Irgarol 1051 EC50: 1.3 μg l-1, diuron EC50: 2.8 μg l-1), Time-course experiments indicated that ΔF/Fm′ was rapidly reduced (i.e. within minutes) in S. hystrix exposed to Irgarol 1051 and diuron. On return to fresh running seawater, ΔF/Fm′ recovered quickly in diuron-exposed corals (i.e. in minutes to hours), but slowly in corals exposed to Irgarol 1051 (i.e. hours to days). Time-course experiments indicated that the effects of diuron (3 μg l-1) on S. hystrix were inversely related to temperature over the range 20 to 30 °C, although initially the effects were less at the lower temperatures. Repeated exposure to pulses of Irgarol 1051 (daily 2 h exposure to 30 μg l -1 over 4 d) resulted in a 30% decrease in the density of symbiotic dinoflagellates in the tissues of S. hystrix.

The agricultural water supply challenge - the need for improved water use efficiency

This paper examines the challenges of water supply in agriculture, with particular emphasis on requirements of field crops, including maize. It places the issue of water supply to agriculture in the context of increasing demands for water from alternatives users, declining quality water, pressure of increasing population, all of which are placing stresses on water availability at local, regional and national levels. The paper also examines existing freshwater resources and the potential impact of climate change on water supply and distribution and consequential impact on water stress incidence in various parts of the globe. It examines competition for water in both industrialized and developing countries, with particular emphasis on the impacts on agriculture and food supplies. The challenge of water use efficiency (WUE) in agriculture is explored with discussion of agronomic, economic and physiological WUE concepts, with specific reference to maize.